Software engineers need to anticipate unintended consequences, including negative impacts on society, individuals, and the environment. Even developers with the best of intentions can walk into ethical traps. This article includes four suggestions for software engineers during system development to help recognize these traps: (1) Look for humans values in technical decisions. (2) Identify stakeholdersgroups and individuals likely to be affected by the system. (3) Examine how the system will affect the stakeholders' rights and obligations. (4) Review relevant professional standards.